diff options
28 files changed, 810 insertions, 160 deletions
diff --git a/Documentation/devicetree/bindings/pwm/adi,axi-pwmgen.yaml b/Documentation/devicetree/bindings/pwm/adi,axi-pwmgen.yaml new file mode 100644 index 000000000000..ec6115d3796b --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/adi,axi-pwmgen.yaml @@ -0,0 +1,48 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pwm/adi,axi-pwmgen.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices AXI PWM generator + +maintainers: + - Michael Hennerich <[email protected]> + - Nuno Sá <[email protected]> + +description: + The Analog Devices AXI PWM generator can generate PWM signals + with variable pulse width and period. + + https://wiki.analog.com/resources/fpga/docs/axi_pwm_gen + +allOf: + - $ref: pwm.yaml# + +properties: + compatible: + const: adi,axi-pwmgen-2.00.a + + reg: + maxItems: 1 + + "#pwm-cells": + const: 2 + + clocks: + maxItems: 1 + +required: + - reg + - clocks + +unevaluatedProperties: false + +examples: + - | + pwm@44b00000 { + compatible = "adi,axi-pwmgen-2.00.a"; + reg = <0x44b00000 0x1000>; + clocks = <&spi_clk>; + #pwm-cells = <2>; + }; diff --git a/Documentation/devicetree/bindings/pwm/fsl,vf610-ftm-pwm.yaml b/Documentation/devicetree/bindings/pwm/fsl,vf610-ftm-pwm.yaml new file mode 100644 index 000000000000..7f9f72d95e7a --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/fsl,vf610-ftm-pwm.yaml @@ -0,0 +1,92 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pwm/fsl,vf610-ftm-pwm.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Freescale FlexTimer Module (FTM) PWM controller + +description: | + The same FTM PWM device can have a different endianness on different SoCs. The + device tree provides a property to describing this so that an operating system + device driver can handle all variants of the device. Refer to the table below + for the endianness of the FTM PWM block as integrated into the existing SoCs: + + SoC | FTM-PWM endianness + --------+------------------- + Vybrid | LE + LS1 | BE + LS2 | LE + + Please see ../regmap/regmap.txt for more detail about how to specify endian + modes in device tree. + +maintainers: + - Frank Li <[email protected]> + +properties: + compatible: + enum: + - fsl,vf610-ftm-pwm + - fsl,imx8qm-ftm-pwm + + reg: + maxItems: 1 + + "#pwm-cells": + const: 3 + + clocks: + minItems: 4 + maxItems: 4 + + clock-names: + items: + - const: ftm_sys + - const: ftm_ext + - const: ftm_fix + - const: ftm_cnt_clk_en + + pinctrl-0: true + pinctrl-1: true + + pinctrl-names: + minItems: 1 + items: + - const: default + - const: sleep + + big-endian: + $ref: /schemas/types.yaml#/definitions/flag + description: + Boolean property, required if the FTM PWM registers use a big- + endian rather than little-endian layout. + +required: + - compatible + - reg + - clocks + - clock-names + +allOf: + - $ref: pwm.yaml# + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/clock/vf610-clock.h> + + pwm@40038000 { + compatible = "fsl,vf610-ftm-pwm"; + reg = <0x40038000 0x1000>; + #pwm-cells = <3>; + clocks = <&clks VF610_CLK_FTM0>, + <&clks VF610_CLK_FTM0_EXT_SEL>, + <&clks VF610_CLK_FTM0_FIX_SEL>, + <&clks VF610_CLK_FTM0_EXT_FIX_EN>; + clock-names = "ftm_sys", "ftm_ext", "ftm_fix", "ftm_cnt_clk_en"; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_pwm0_1>; + big-endian; + }; diff --git a/Documentation/devicetree/bindings/pwm/imx-pwm.yaml b/Documentation/devicetree/bindings/pwm/imx-pwm.yaml index a84a240a61dc..04148198e34d 100644 --- a/Documentation/devicetree/bindings/pwm/imx-pwm.yaml +++ b/Documentation/devicetree/bindings/pwm/imx-pwm.yaml @@ -68,7 +68,6 @@ required: - reg - clocks - clock-names - - interrupts additionalProperties: false diff --git a/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt b/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt deleted file mode 100644 index 36532cd5ab25..000000000000 --- a/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt +++ /dev/null @@ -1,55 +0,0 @@ -Freescale FlexTimer Module (FTM) PWM controller - -The same FTM PWM device can have a different endianness on different SoCs. The -device tree provides a property to describing this so that an operating system -device driver can handle all variants of the device. Refer to the table below -for the endianness of the FTM PWM block as integrated into the existing SoCs: - - SoC | FTM-PWM endianness - --------+------------------- - Vybrid | LE - LS1 | BE - LS2 | LE - -Please see ../regmap/regmap.txt for more detail about how to specify endian -modes in device tree. - - -Required properties: -- compatible : should be "fsl,<soc>-ftm-pwm" and one of the following - compatible strings: - - "fsl,vf610-ftm-pwm" for PWM compatible with the one integrated on VF610 - - "fsl,imx8qm-ftm-pwm" for PWM compatible with the one integrated on i.MX8QM -- reg: Physical base address and length of the controller's registers -- #pwm-cells: Should be 3. See pwm.yaml in this directory for a description of - the cells format. -- clock-names: Should include the following module clock source entries: - "ftm_sys" (module clock, also can be used as counter clock), - "ftm_ext" (external counter clock), - "ftm_fix" (fixed counter clock), - "ftm_cnt_clk_en" (external and fixed counter clock enable/disable). -- clocks: Must contain a phandle and clock specifier for each entry in - clock-names, please see clock/clock-bindings.txt for details of the property - values. -- pinctrl-names: Must contain a "default" entry. -- pinctrl-NNN: One property must exist for each entry in pinctrl-names. - See pinctrl/pinctrl-bindings.txt for details of the property values. -- big-endian: Boolean property, required if the FTM PWM registers use a big- - endian rather than little-endian layout. - -Example: - -pwm0: pwm@40038000 { - compatible = "fsl,vf610-ftm-pwm"; - reg = <0x40038000 0x1000>; - #pwm-cells = <3>; - clock-names = "ftm_sys", "ftm_ext", - "ftm_fix", "ftm_cnt_clk_en"; - clocks = <&clks VF610_CLK_FTM0>, - <&clks VF610_CLK_FTM0_EXT_SEL>, - <&clks VF610_CLK_FTM0_FIX_SEL>, - <&clks VF610_CLK_FTM0_EXT_FIX_EN>; - pinctrl-names = "default"; - pinctrl-0 = <&pinctrl_pwm0_1>; - big-endian; -}; diff --git a/Documentation/devicetree/bindings/pwm/pwm-gpio.yaml b/Documentation/devicetree/bindings/pwm/pwm-gpio.yaml new file mode 100644 index 000000000000..1576c193f2ab --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/pwm-gpio.yaml @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pwm/pwm-gpio.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic software PWM for modulating GPIOs + +maintainers: + - Stefan Wahren <[email protected]> + +allOf: + - $ref: pwm.yaml# + +properties: + compatible: + const: pwm-gpio + + "#pwm-cells": + const: 3 + description: + See pwm.yaml in this directory for a description of the cells format. + The first cell which represents the PWM instance number must always + be zero. + + gpios: + description: + GPIO to be modulated + maxItems: 1 + +required: + - compatible + - "#pwm-cells" + - gpios + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + + pwm { + #pwm-cells = <3>; + compatible = "pwm-gpio"; + gpios = <&gpio 1 GPIO_ACTIVE_HIGH>; + }; diff --git a/Documentation/devicetree/bindings/pwm/pwm.yaml b/Documentation/devicetree/bindings/pwm/pwm.yaml index abd9fa873354..f2206ec3c7c4 100644 --- a/Documentation/devicetree/bindings/pwm/pwm.yaml +++ b/Documentation/devicetree/bindings/pwm/pwm.yaml @@ -16,8 +16,10 @@ properties: pattern: "^pwm(@.*|-([0-9]|[1-9][0-9]+))?$" "#pwm-cells": - description: - Number of cells in a PWM specifier. + description: | + Number of cells in a PWM specifier. Typically the cells represent, in + order: the chip-relative PWM number, the PWM period in nanoseconds and + optionally a number of flags (defined in <dt-bindings/pwm/pwm.h>). required: - "#pwm-cells" diff --git a/Documentation/driver-api/gpio/drivers-on-gpio.rst b/Documentation/driver-api/gpio/drivers-on-gpio.rst index af632d764ac6..95572d2a94ce 100644 --- a/Documentation/driver-api/gpio/drivers-on-gpio.rst +++ b/Documentation/driver-api/gpio/drivers-on-gpio.rst @@ -27,7 +27,12 @@ hardware descriptions such as device tree or ACPI: to the lines for a more permanent solution of this type. - gpio-beeper: drivers/input/misc/gpio-beeper.c is used to provide a beep from - an external speaker connected to a GPIO line. + an external speaker connected to a GPIO line. (If the beep is controlled by + off/on, for an actual PWM waveform, see pwm-gpio below.) + +- pwm-gpio: drivers/pwm/pwm-gpio.c is used to toggle a GPIO with a high + resolution timer producing a PWM waveform on the GPIO line, as well as + Linux high resolution timers can do. - extcon-gpio: drivers/extcon/extcon-gpio.c is used when you need to read an external connector status, such as a headset line for an audio driver or an diff --git a/MAINTAINERS b/MAINTAINERS index d6c90161c7bf..ebe38fd0b5b7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3571,6 +3571,15 @@ W: https://ez.analog.com/linux-software-drivers F: Documentation/devicetree/bindings/spi/adi,axi-spi-engine.yaml F: drivers/spi/spi-axi-spi-engine.c +AXI PWM GENERATOR +M: Michael Hennerich <[email protected]> +M: Nuno Sá <[email protected]> +S: Supported +W: https://ez.analog.com/linux-software-drivers +F: Documentation/devicetree/bindings/pwm/adi,axi-pwmgen.yaml +F: drivers/pwm/pwm-axi-pwmgen.c + AXXIA I2C CONTROLLER M: Krzysztof Adamski <[email protected]> diff --git a/drivers/bus/ts-nbus.c b/drivers/bus/ts-nbus.c index baf22a82c47a..b8af44c5cdbd 100644 --- a/drivers/bus/ts-nbus.c +++ b/drivers/bus/ts-nbus.c @@ -294,7 +294,7 @@ static int ts_nbus_probe(struct platform_device *pdev) state.duty_cycle = state.period; state.enabled = true; - ret = pwm_apply_state(pwm, &state); + ret = pwm_apply_might_sleep(pwm, &state); if (ret < 0) return dev_err_probe(dev, ret, "failed to configure PWM\n"); diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 1dd7921194f5..3e53838990f5 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -94,6 +94,19 @@ config PWM_ATMEL_TCB To compile this driver as a module, choose M here: the module will be called pwm-atmel-tcb. +config PWM_AXI_PWMGEN + tristate "Analog Devices AXI PWM generator" + depends on MICROBLAZE || NIOS2 || ARCH_ZYNQ || ARCH_ZYNQMP || ARCH_INTEL_SOCFPGA || COMPILE_TEST + select REGMAP_MMIO + help + This enables support for the Analog Devices AXI PWM generator. + + This is a configurable PWM generator with variable pulse width and + period. + + To compile this driver as a module, choose M here: the module will be + called pwm-axi-pwmgen. + config PWM_BCM_IPROC tristate "iProc PWM support" depends on ARCH_BCM_IPROC || COMPILE_TEST @@ -223,6 +236,17 @@ config PWM_FSL_FTM To compile this driver as a module, choose M here: the module will be called pwm-fsl-ftm. +config PWM_GPIO + tristate "GPIO PWM support" + depends on GPIOLIB + depends on HIGH_RES_TIMERS + help + Generic PWM framework driver for software PWM toggling a GPIO pin + from kernel high-resolution timers. + + To compile this driver as a module, choose M here: the module + will be called pwm-gpio. + config PWM_HIBVT tristate "HiSilicon BVT PWM support" depends on ARCH_HISI || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 90913519f11a..0be4f3e6dd43 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_PWM_APPLE) += pwm-apple.o obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM) += pwm-atmel-hlcdc.o obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o +obj-$(CONFIG_PWM_AXI_PWMGEN) += pwm-axi-pwmgen.o obj-$(CONFIG_PWM_BCM_IPROC) += pwm-bcm-iproc.o obj-$(CONFIG_PWM_BCM_KONA) += pwm-bcm-kona.o obj-$(CONFIG_PWM_BCM2835) += pwm-bcm2835.o @@ -18,6 +19,7 @@ obj-$(CONFIG_PWM_DWC_CORE) += pwm-dwc-core.o obj-$(CONFIG_PWM_DWC) += pwm-dwc.o obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o +obj-$(CONFIG_PWM_GPIO) += pwm-gpio.o obj-$(CONFIG_PWM_HIBVT) += pwm-hibvt.o obj-$(CONFIG_PWM_IMG) += pwm-img.o obj-$(CONFIG_PWM_IMX1) += pwm-imx1.o diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 18574857641e..5c1d20985148 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -6,6 +6,8 @@ * Copyright (C) 2011-2012 Avionic Design GmbH */ +#define DEFAULT_SYMBOL_NAMESPACE PWM + #include <linux/acpi.h> #include <linux/module.h> #include <linux/idr.h> @@ -394,9 +396,9 @@ err_get_device: * chip. A negative error code is returned if the index is not valid for the * specified PWM chip or if the PWM device cannot be requested. */ -struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, - unsigned int index, - const char *label) +static struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, + unsigned int index, + const char *label) { struct pwm_device *pwm; int err; @@ -414,8 +416,6 @@ struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, mutex_unlock(&pwm_lock); return pwm; } -EXPORT_SYMBOL_GPL(pwm_request_from_chip); - struct pwm_device * of_pwm_xlate_with_flags(struct pwm_chip *chip, const struct of_phandle_args *args) diff --git a/drivers/pwm/pwm-atmel-tcb.c b/drivers/pwm/pwm-atmel-tcb.c index 528e54c5999d..aca11493239a 100644 --- a/drivers/pwm/pwm-atmel-tcb.c +++ b/drivers/pwm/pwm-atmel-tcb.c @@ -81,7 +81,8 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip, tcbpwm->period = 0; tcbpwm->div = 0; - spin_lock(&tcbpwmc->lock); + guard(spinlock)(&tcbpwmc->lock); + regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), &cmr); /* * Get init config from Timer Counter registers if @@ -107,7 +108,6 @@ static int atmel_tcb_pwm_request(struct pwm_chip *chip, cmr |= ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO | ATMEL_TC_EEVT_XC0; regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), cmr); - spin_unlock(&tcbpwmc->lock); return 0; } @@ -137,7 +137,6 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm, if (tcbpwm->duty == 0) polarity = !polarity; - spin_lock(&tcbpwmc->lock); regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), &cmr); /* flush old setting and set the new one */ @@ -172,8 +171,6 @@ static void atmel_tcb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm, ATMEL_TC_SWTRG); tcbpwmc->bkup.enabled = 0; } - - spin_unlock(&tcbpwmc->lock); } static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, @@ -194,7 +191,6 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, if (tcbpwm->duty == 0) polarity = !polarity; - spin_lock(&tcbpwmc->lock); regmap_read(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CMR), &cmr); /* flush old setting and set the new one */ @@ -256,7 +252,6 @@ static int atmel_tcb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, regmap_write(tcbpwmc->regmap, ATMEL_TC_REG(tcbpwmc->channel, CCR), ATMEL_TC_SWTRG | ATMEL_TC_CLKEN); tcbpwmc->bkup.enabled = 1; - spin_unlock(&tcbpwmc->lock); return 0; } @@ -341,9 +336,12 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, static int atmel_tcb_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { + struct atmel_tcb_pwm_chip *tcbpwmc = to_tcb_chip(chip); int duty_cycle, period; int ret; + guard(spinlock)(&tcbpwmc->lock); + if (!state->enabled) { atmel_tcb_pwm_disable(chip, pwm, state->polarity); return 0; diff --git a/drivers/pwm/pwm-axi-pwmgen.c b/drivers/pwm/pwm-axi-pwmgen.c new file mode 100644 index 000000000000..aac4f395497b --- /dev/null +++ b/drivers/pwm/pwm-axi-pwmgen.c @@ -0,0 +1,241 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Analog Devices AXI PWM generator + * + * Copyright 2024 Analog Devices Inc. + * Copyright 2024 Baylibre SAS + * + * Device docs: https://analogdevicesinc.github.io/hdl/library/axi_pwm_gen/index.html + * + * Limitations: + * - The writes to registers for period and duty are shadowed until + * LOAD_CONFIG is written to AXI_PWMGEN_REG_CONFIG, at which point + * they take effect. + * - Writing LOAD_CONFIG also has the effect of re-synchronizing all + * enabled channels, which could cause glitching on other channels. It + * is therefore expected that channels are assigned harmonic periods + * and all have a single user coordinating this. + * - Supports normal polarity. Does not support changing polarity. + * - On disable, the PWM output becomes low (inactive). + */ +#include <linux/bits.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/fpga/adi-axi-common.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define AXI_PWMGEN_REG_CORE_VERSION 0x00 +#define AXI_PWMGEN_REG_ID 0x04 +#define AXI_PWMGEN_REG_SCRATCHPAD 0x08 +#define AXI_PWMGEN_REG_CORE_MAGIC 0x0C +#define AXI_PWMGEN_REG_CONFIG 0x10 +#define AXI_PWMGEN_REG_NPWM 0x14 +#define AXI_PWMGEN_CHX_PERIOD(ch) (0x40 + (4 * (ch))) +#define AXI_PWMGEN_CHX_DUTY(ch) (0x80 + (4 * (ch))) +#define AXI_PWMGEN_CHX_OFFSET(ch) (0xC0 + (4 * (ch))) +#define AXI_PWMGEN_REG_CORE_MAGIC_VAL 0x601A3471 /* Identification number to test during setup */ +#define AXI_PWMGEN_LOAD_CONFIG BIT(1) +#define AXI_PWMGEN_REG_CONFIG_RESET BIT(0) + +struct axi_pwmgen_ddata { + struct regmap *regmap; + unsigned long clk_rate_hz; +}; + +static const struct regmap_config axi_pwmgen_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, +}; + +static int axi_pwmgen_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct axi_pwmgen_ddata *ddata = pwmchip_get_drvdata(chip); + unsigned int ch = pwm->hwpwm; + struct regmap *regmap = ddata->regmap; + u64 period_cnt, duty_cnt; + int ret; + + if (state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + if (state->enabled) { + period_cnt = mul_u64_u64_div_u64(state->period, ddata->clk_rate_hz, NSEC_PER_SEC); + if (period_cnt > UINT_MAX) + period_cnt = UINT_MAX; + + if (period_cnt == 0) + return -EINVAL; + + ret = regmap_write(regmap, AXI_PWMGEN_CHX_PERIOD(ch), period_cnt); + if (ret) + return ret; + + duty_cnt = mul_u64_u64_div_u64(state->duty_cycle, ddata->clk_rate_hz, NSEC_PER_SEC); + if (duty_cnt > UINT_MAX) + duty_cnt = UINT_MAX; + + ret = regmap_write(regmap, AXI_PWMGEN_CHX_DUTY(ch), duty_cnt); + if (ret) + return ret; + } else { + ret = regmap_write(regmap, AXI_PWMGEN_CHX_PERIOD(ch), 0); + if (ret) + return ret; + + ret = regmap_write(regmap, AXI_PWMGEN_CHX_DUTY(ch), 0); + if (ret) + return ret; + } + + return regmap_write(regmap, AXI_PWMGEN_REG_CONFIG, AXI_PWMGEN_LOAD_CONFIG); +} + +static int axi_pwmgen_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct axi_pwmgen_ddata *ddata = pwmchip_get_drvdata(chip); + struct regmap *regmap = ddata->regmap; + unsigned int ch = pwm->hwpwm; + u32 cnt; + int ret; + + ret = regmap_read(regmap, AXI_PWMGEN_CHX_PERIOD(ch), &cnt); + if (ret) + return ret; + + state->enabled = cnt != 0; + + state->period = DIV_ROUND_UP_ULL((u64)cnt * NSEC_PER_SEC, ddata->clk_rate_hz); + + ret = regmap_read(regmap, AXI_PWMGEN_CHX_DUTY(ch), &cnt); + if (ret) + return ret; + + state->duty_cycle = DIV_ROUND_UP_ULL((u64)cnt * NSEC_PER_SEC, ddata->clk_rate_hz); + + state->polarity = PWM_POLARITY_NORMAL; + + return 0; +} + +static const struct pwm_ops axi_pwmgen_pwm_ops = { + .apply = axi_pwmgen_apply, + .get_state = axi_pwmgen_get_state, +}; + +static int axi_pwmgen_setup(struct regmap *regmap, struct device *dev) +{ + int ret; + u32 val; + + ret = regmap_read(regmap, AXI_PWMGEN_REG_CORE_MAGIC, &val); + if (ret) + return ret; + + if (val != AXI_PWMGEN_REG_CORE_MAGIC_VAL) + return dev_err_probe(dev, -ENODEV, + "failed to read expected value from register: got %08x, expected %08x\n", + val, AXI_PWMGEN_REG_CORE_MAGIC_VAL); + + ret = regmap_read(regmap, AXI_PWMGEN_REG_CORE_VERSION, &val); + if (ret) + return ret; + + if (ADI_AXI_PCORE_VER_MAJOR(val) != 2) { + return dev_err_probe(dev, -ENODEV, "Unsupported peripheral version %u.%u.%u\n", + ADI_AXI_PCORE_VER_MAJOR(val), + ADI_AXI_PCORE_VER_MINOR(val), + ADI_AXI_PCORE_VER_PATCH(val)); + } + + /* Enable the core */ + ret = regmap_clear_bits(regmap, AXI_PWMGEN_REG_CONFIG, AXI_PWMGEN_REG_CONFIG_RESET); + if (ret) + return ret; + + ret = regmap_read(regmap, AXI_PWMGEN_REG_NPWM, &val); + if (ret) + return ret; + + /* Return the number of PWMs */ + return val; +} + +static int axi_pwmgen_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct regmap *regmap; + struct pwm_chip *chip; + struct axi_pwmgen_ddata *ddata; + struct clk *clk; + void __iomem *io_base; + int ret; + + io_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(io_base)) + return PTR_ERR(io_base); + + regmap = devm_regmap_init_mmio(dev, io_base, &axi_pwmgen_regmap_config); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), + "failed to init register map\n"); + + ret = axi_pwmgen_setup(regmap, dev); + if (ret < 0) + return ret; + + chip = devm_pwmchip_alloc(dev, ret, sizeof(*ddata)); + if (IS_ERR(chip)) + return PTR_ERR(chip); + ddata = pwmchip_get_drvdata(chip); + ddata->regmap = regmap; + + clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(clk)) + return dev_err_probe(dev, PTR_ERR(clk), "failed to get clock\n"); + + ret = devm_clk_rate_exclusive_get(dev, clk); + if (ret) + return dev_err_probe(dev, ret, "failed to get exclusive rate\n"); + + ddata->clk_rate_hz = clk_get_rate(clk); + if (!ddata->clk_rate_hz || ddata->clk_rate_hz > NSEC_PER_SEC) + return dev_err_probe(dev, -EINVAL, + "Invalid clock rate: %lu\n", ddata->clk_rate_hz); + + chip->ops = &axi_pwmgen_pwm_ops; + chip->atomic = true; + + ret = devm_pwmchip_add(dev, chip); + if (ret) + return dev_err_probe(dev, ret, "could not add PWM chip\n"); + + return 0; +} + +static const struct of_device_id axi_pwmgen_ids[] = { + { .compatible = "adi,axi-pwmgen-2.00.a" }, + { } +}; +MODULE_DEVICE_TABLE(of, axi_pwmgen_ids); + +static struct platform_driver axi_pwmgen_driver = { + .driver = { + .name = "axi-pwmgen", + .of_match_table = axi_pwmgen_ids, + }, + .probe = axi_pwmgen_probe, +}; +module_platform_driver(axi_pwmgen_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sergiu Cuciurean <[email protected]>"); +MODULE_AUTHOR("Trevor Gamblin <[email protected]>"); +MODULE_DESCRIPTION("Driver for the Analog Devices AXI PWM generator"); diff --git a/drivers/pwm/pwm-cros-ec.c b/drivers/pwm/pwm-cros-ec.c index 606ccfdaf4cc..189301dc395e 100644 --- a/drivers/pwm/pwm-cros-ec.c +++ b/drivers/pwm/pwm-cros-ec.c @@ -20,20 +20,10 @@ * * @ec: Pointer to EC device * @use_pwm_type: Use PWM types instead of generic channels - * @channel: array with per-channel data */ struct cros_ec_pwm_device { struct cros_ec_device *ec; bool use_pwm_type; - struct cros_ec_pwm *channel; -}; - -/** - * struct cros_ec_pwm - per-PWM driver data - * @duty_cycle: cached duty cycle - */ -struct cros_ec_pwm { - u16 duty_cycle; }; static inline struct cros_ec_pwm_device *pwm_to_cros_ec_pwm(struct pwm_chip *chip) @@ -135,7 +125,6 @@ static int cros_ec_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { struct cros_ec_pwm_device *ec_pwm = pwm_to_cros_ec_pwm(chip); - struct cros_ec_pwm *channel = &ec_pwm->channel[pwm->hwpwm]; u16 duty_cycle; int ret; @@ -156,8 +145,6 @@ static int cros_ec_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, if (ret < 0) return ret; - channel->duty_cycle = state->duty_cycle; - return 0; } @@ -165,7 +152,6 @@ static int cros_ec_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state) { struct cros_ec_pwm_device *ec_pwm = pwm_to_cros_ec_pwm(chip); - struct cros_ec_pwm *channel = &ec_pwm->channel[pwm->hwpwm]; int ret; ret = cros_ec_pwm_get_duty(ec_pwm->ec, ec_pwm->use_pwm_type, pwm->hwpwm); @@ -175,44 +161,13 @@ static int cros_ec_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, } state->enabled = (ret > 0); + state->duty_cycle = ret; state->period = EC_PWM_MAX_DUTY; state->polarity = PWM_POLARITY_NORMAL; - /* - * Note that "disabled" and "duty cycle == 0" are treated the same. If - * the cached duty cycle is not zero, used the cached duty cycle. This - * ensures that the configured duty cycle is kept across a disable and - * enable operation and avoids potentially confusing consumers. - * - * For the case of the initial hardware readout, channel->duty_cycle - * will be 0 and the actual duty cycle read from the EC is used. - */ - if (ret == 0 && channel->duty_cycle > 0) - state->duty_cycle = channel->duty_cycle; - else - state->duty_cycle = ret; - return 0; } -static struct pwm_device * -cros_ec_pwm_xlate(struct pwm_chip *chip, const struct of_phandle_args *args) -{ - struct pwm_device *pwm; - - if (args->args[0] >= chip->npwm) - return ERR_PTR(-EINVAL); - - pwm = pwm_request_from_chip(chip, args->args[0], NULL); - if (IS_ERR(pwm)) - return pwm; - - /* The EC won't let us change the period */ - pwm->args.period = EC_PWM_MAX_DUTY; - - return pwm; -} - static const struct pwm_ops cros_ec_pwm_ops = { .get_state = cros_ec_pwm_get_state, .apply = cros_ec_pwm_apply, @@ -263,7 +218,7 @@ static int cros_ec_pwm_probe(struct platform_device *pdev) struct cros_ec_pwm_device *ec_pwm; struct pwm_chip *chip; bool use_pwm_type = false; - unsigned int npwm; + unsigned int i, npwm; int ret; if (!ec) @@ -289,12 +244,17 @@ static int cros_ec_pwm_probe(struct platform_device *pdev) /* PWM chip */ chip->ops = &cros_ec_pwm_ops; - chip->of_xlate = cros_ec_pwm_xlate; - ec_pwm->channel = devm_kcalloc(dev, chip->npwm, sizeof(*ec_pwm->channel), - GFP_KERNEL); - if (!ec_pwm->channel) - return -ENOMEM; + /* + * The device tree binding for this device is special as it only uses a + * single cell (for the hwid) and so doesn't provide a default period. + * This isn't a big problem though as the hardware only supports a + * single period length, it's just a bit ugly to make this fit into the + * pwm core abstractions. So initialize the period here, as + * of_pwm_xlate_with_flags() won't do that for us. + */ + for (i = 0; i < npwm; ++i) + chip->pwms[i].args.period = EC_PWM_MAX_DUTY; dev_dbg(dev, "Probed %u PWMs\n", chip->npwm); diff --git a/drivers/pwm/pwm-gpio.c b/drivers/pwm/pwm-gpio.c new file mode 100644 index 000000000000..9f8884ac7504 --- /dev/null +++ b/drivers/pwm/pwm-gpio.c @@ -0,0 +1,241 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Generic software PWM for modulating GPIOs + * + * Copyright (C) 2020 Axis Communications AB + * Copyright (C) 2020 Nicola Di Lieto + * Copyright (C) 2024 Stefan Wahren + * Copyright (C) 2024 Linus Walleij + */ + +#include <linux/cleanup.h> +#include <linux/container_of.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/hrtimer.h> +#include <linux/math.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/pwm.h> +#include <linux/spinlock.h> +#include <linux/time.h> +#include <linux/types.h> + +struct pwm_gpio { + struct hrtimer gpio_timer; + struct gpio_desc *gpio; + struct pwm_state state; + struct pwm_state next_state; + + /* Protect internal state between pwm_ops and hrtimer */ + spinlock_t lock; + + bool changing; + bool running; + bool level; +}; + +static void pwm_gpio_round(struct pwm_state *dest, const struct pwm_state *src) +{ + u64 dividend; + u32 remainder; + + *dest = *src; + + /* Round down to hrtimer resolution */ + dividend = dest->period; + remainder = do_div(dividend, hrtimer_resolution); + dest->period -= remainder; + + dividend = dest->duty_cycle; + remainder = do_div(dividend, hrtimer_resolution); + dest->duty_cycle -= remainder; +} + +static u64 pwm_gpio_toggle(struct pwm_gpio *gpwm, bool level) +{ + const struct pwm_state *state = &gpwm->state; + bool invert = state->polarity == PWM_POLARITY_INVERSED; + + gpwm->level = level; + gpiod_set_value(gpwm->gpio, gpwm->level ^ invert); + + if (!state->duty_cycle || state->duty_cycle == state->period) { + gpwm->running = false; + return 0; + } + + gpwm->running = true; + return level ? state->duty_cycle : state->period - state->duty_cycle; +} + +static enum hrtimer_restart pwm_gpio_timer(struct hrtimer *gpio_timer) +{ + struct pwm_gpio *gpwm = container_of(gpio_timer, struct pwm_gpio, + gpio_timer); + u64 next_toggle; + bool new_level; + + guard(spinlock_irqsave)(&gpwm->lock); + + /* Apply new state at end of current period */ + if (!gpwm->level && gpwm->changing) { + gpwm->changing = false; + gpwm->state = gpwm->next_state; + new_level = !!gpwm->state.duty_cycle; + } else { + new_level = !gpwm->level; + } + + next_toggle = pwm_gpio_toggle(gpwm, new_level); + if (next_toggle) + hrtimer_forward(gpio_timer, hrtimer_get_expires(gpio_timer), + ns_to_ktime(next_toggle)); + + return next_toggle ? HRTIMER_RESTART : HRTIMER_NORESTART; +} + +static int pwm_gpio_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct pwm_gpio *gpwm = pwmchip_get_drvdata(chip); + bool invert = state->polarity == PWM_POLARITY_INVERSED; + + if (state->duty_cycle && state->duty_cycle < hrtimer_resolution) + return -EINVAL; + + if (state->duty_cycle != state->period && + (state->period - state->duty_cycle < hrtimer_resolution)) + return -EINVAL; + + if (!state->enabled) { + hrtimer_cancel(&gpwm->gpio_timer); + } else if (!gpwm->running) { + int ret; + + /* + * This just enables the output, but pwm_gpio_toggle() + * really starts the duty cycle. + */ + ret = gpiod_direction_output(gpwm->gpio, invert); + if (ret) + return ret; + } + + guard(spinlock_irqsave)(&gpwm->lock); + + if (!state->enabled) { + pwm_gpio_round(&gpwm->state, state); + gpwm->running = false; + gpwm->changing = false; + + gpiod_set_value(gpwm->gpio, invert); + } else if (gpwm->running) { + pwm_gpio_round(&gpwm->next_state, state); + gpwm->changing = true; + } else { + unsigned long next_toggle; + + pwm_gpio_round(&gpwm->state, state); + gpwm->changing = false; + + next_toggle = pwm_gpio_toggle(gpwm, !!state->duty_cycle); + if (next_toggle) + hrtimer_start(&gpwm->gpio_timer, next_toggle, + HRTIMER_MODE_REL); + } + + return 0; +} + +static int pwm_gpio_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct pwm_gpio *gpwm = pwmchip_get_drvdata(chip); + + guard(spinlock_irqsave)(&gpwm->lock); + + if (gpwm->changing) + *state = gpwm->next_state; + else + *state = gpwm->state; + + return 0; +} + +static const struct pwm_ops pwm_gpio_ops = { + .apply = pwm_gpio_apply, + .get_state = pwm_gpio_get_state, +}; + +static void pwm_gpio_disable_hrtimer(void *data) +{ + struct pwm_gpio *gpwm = data; + + hrtimer_cancel(&gpwm->gpio_timer); +} + +static int pwm_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct pwm_chip *chip; + struct pwm_gpio *gpwm; + int ret; + + chip = devm_pwmchip_alloc(dev, 1, sizeof(*gpwm)); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + gpwm = pwmchip_get_drvdata(chip); + + spin_lock_init(&gpwm->lock); + + gpwm->gpio = devm_gpiod_get(dev, NULL, GPIOD_ASIS); + if (IS_ERR(gpwm->gpio)) + return dev_err_probe(dev, PTR_ERR(gpwm->gpio), + "%pfw: could not get gpio\n", + dev_fwnode(dev)); + + if (gpiod_cansleep(gpwm->gpio)) + return dev_err_probe(dev, -EINVAL, + "%pfw: sleeping GPIO not supported\n", + dev_fwnode(dev)); + + chip->ops = &pwm_gpio_ops; + chip->atomic = true; + + hrtimer_init(&gpwm->gpio_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + ret = devm_add_action_or_reset(dev, pwm_gpio_disable_hrtimer, gpwm); + if (ret) + return ret; + + gpwm->gpio_timer.function = pwm_gpio_timer; + + ret = pwmchip_add(chip); + if (ret < 0) + return dev_err_probe(dev, ret, "could not add pwmchip\n"); + + return 0; +} + +static const struct of_device_id pwm_gpio_dt_ids[] = { + { .compatible = "pwm-gpio" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, pwm_gpio_dt_ids); + +static struct platform_driver pwm_gpio_driver = { + .driver = { + .name = "pwm-gpio", + .of_match_table = pwm_gpio_dt_ids, + }, + .probe = pwm_gpio_probe, +}; +module_platform_driver(pwm_gpio_driver); + +MODULE_DESCRIPTION("PWM GPIO driver"); +MODULE_AUTHOR("Vincent Whitchurch"); +MODULE_LICENSE("GPL"); diff --git a/drivers/pwm/pwm-imx1.c b/drivers/pwm/pwm-imx1.c index 1d2aae2d278f..d5535d208005 100644 --- a/drivers/pwm/pwm-imx1.c +++ b/drivers/pwm/pwm-imx1.c @@ -194,5 +194,6 @@ static struct platform_driver pwm_imx1_driver = { }; module_platform_driver(pwm_imx1_driver); +MODULE_DESCRIPTION("i.MX1 and i.MX21 Pulse Width Modulator driver"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Sascha Hauer <[email protected]>"); diff --git a/drivers/pwm/pwm-imx27.c b/drivers/pwm/pwm-imx27.c index e1412116ef65..9e2bbf5b4a8c 100644 --- a/drivers/pwm/pwm-imx27.c +++ b/drivers/pwm/pwm-imx27.c @@ -352,5 +352,6 @@ static struct platform_driver imx_pwm_driver = { }; module_platform_driver(imx_pwm_driver); +MODULE_DESCRIPTION("i.MX27 and later i.MX SoCs Pulse Width Modulator driver"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Sascha Hauer <[email protected]>"); diff --git a/drivers/pwm/pwm-intel-lgm.c b/drivers/pwm/pwm-intel-lgm.c index f9cc7c17c8f0..084c71a0a11b 100644 --- a/drivers/pwm/pwm-intel-lgm.c +++ b/drivers/pwm/pwm-intel-lgm.c @@ -230,4 +230,5 @@ static struct platform_driver lgm_pwm_driver = { }; module_platform_driver(lgm_pwm_driver); +MODULE_DESCRIPTION("Intel LGM Pulse Width Modulator driver"); MODULE_LICENSE("GPL v2"); diff --git a/drivers/pwm/pwm-jz4740.c b/drivers/pwm/pwm-jz4740.c index da4bf543d357..6bdb01619380 100644 --- a/drivers/pwm/pwm-jz4740.c +++ b/drivers/pwm/pwm-jz4740.c @@ -201,12 +201,11 @@ static int jz4740_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, * state instead of its inactive state. */ if ((state->polarity == PWM_POLARITY_NORMAL) ^ state->enabled) - regmap_update_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), - TCU_TCSR_PWM_INITL_HIGH, 0); + regmap_clear_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), + TCU_TCSR_PWM_INITL_HIGH); else - regmap_update_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), - TCU_TCSR_PWM_INITL_HIGH, - TCU_TCSR_PWM_INITL_HIGH); + regmap_set_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), + TCU_TCSR_PWM_INITL_HIGH); if (state->enabled) jz4740_pwm_enable(chip, pwm); diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c index 19a87873ad60..01dfa0fab80a 100644 --- a/drivers/pwm/pwm-mediatek.c +++ b/drivers/pwm/pwm-mediatek.c @@ -395,4 +395,5 @@ static struct platform_driver pwm_mediatek_driver = { module_platform_driver(pwm_mediatek_driver); MODULE_AUTHOR("John Crispin <[email protected]>"); +MODULE_DESCRIPTION("MediaTek general purpose Pulse Width Modulator driver"); MODULE_LICENSE("GPL v2"); diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c index b2f97dfb01bb..98e6c1533312 100644 --- a/drivers/pwm/pwm-meson.c +++ b/drivers/pwm/pwm-meson.c @@ -460,6 +460,37 @@ static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip) return meson_pwm_init_clocks_meson8b(chip, mux_parent_data); } +static void meson_pwm_s4_put_clk(void *data) +{ + struct clk *clk = data; + + clk_put(clk); +} + +static int meson_pwm_init_channels_s4(struct pwm_chip *chip) +{ + struct device *dev = pwmchip_parent(chip); + struct device_node *np = dev->of_node; + struct meson_pwm *meson = to_meson_pwm(chip); + int i, ret; + + for (i = 0; i < MESON_NUM_PWMS; i++) { + meson->channels[i].clk = of_clk_get(np, i); + if (IS_ERR(meson->channels[i].clk)) + return dev_err_probe(dev, + PTR_ERR(meson->channels[i].clk), + "Failed to get clk\n"); + + ret = devm_add_action_or_reset(dev, meson_pwm_s4_put_clk, + meson->channels[i].clk); + if (ret) + return dev_err_probe(dev, ret, + "Failed to add clk_put action\n"); + } + + return 0; +} + static const struct meson_pwm_data pwm_meson8b_data = { .parent_names = { "xtal", NULL, "fclk_div4", "fclk_div3" }, .channels_init = meson_pwm_init_channels_meson8b_legacy, @@ -498,6 +529,10 @@ static const struct meson_pwm_data pwm_meson8_v2_data = { .channels_init = meson_pwm_init_channels_meson8b_v2, }; +static const struct meson_pwm_data pwm_s4_data = { + .channels_init = meson_pwm_init_channels_s4, +}; + static const struct of_device_id meson_pwm_matches[] = { { .compatible = "amlogic,meson8-pwm-v2", @@ -536,6 +571,10 @@ static const struct of_device_id meson_pwm_matches[] = { .compatible = "amlogic,meson-g12a-ao-pwm-cd", .data = &pwm_g12a_ao_cd_data }, + { + .compatible = "amlogic,meson-s4-pwm", + .data = &pwm_s4_data + }, {}, }; MODULE_DEVICE_TABLE(of, meson_pwm_matches); diff --git a/drivers/pwm/pwm-pxa.c b/drivers/pwm/pwm-pxa.c index bb7bb48b2e6d..430bd6a709e9 100644 --- a/drivers/pwm/pwm-pxa.c +++ b/drivers/pwm/pwm-pxa.c @@ -208,4 +208,5 @@ static struct platform_driver pwm_driver = { module_platform_driver(pwm_driver); +MODULE_DESCRIPTION("PXA Pulse Width Modulator driver"); MODULE_LICENSE("GPL v2"); diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c index efb60c9f0cb3..7adf4f2b1049 100644 --- a/drivers/pwm/pwm-samsung.c +++ b/drivers/pwm/pwm-samsung.c @@ -644,6 +644,7 @@ static struct platform_driver pwm_samsung_driver = { }; module_platform_driver(pwm_samsung_driver); +MODULE_DESCRIPTION("Samsung Pulse Width Modulator driver"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Tomasz Figa <[email protected]>"); MODULE_ALIAS("platform:samsung-pwm"); diff --git a/drivers/pwm/pwm-spear.c b/drivers/pwm/pwm-spear.c index 6c6f3b38c835..4f372279f313 100644 --- a/drivers/pwm/pwm-spear.c +++ b/drivers/pwm/pwm-spear.c @@ -255,6 +255,7 @@ static struct platform_driver spear_pwm_driver = { module_platform_driver(spear_pwm_driver); +MODULE_DESCRIPTION("ST Microelectronics SPEAr Pulse Width Modulator driver"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Shiraz Hashim <[email protected]>"); MODULE_AUTHOR("Viresh Kumar <[email protected]>"); diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c index a2f231d13a9f..c586029caf23 100644 --- a/drivers/pwm/pwm-stm32.c +++ b/drivers/pwm/pwm-stm32.c @@ -321,22 +321,30 @@ static int stm32_pwm_config(struct stm32_pwm *priv, unsigned int ch, * First we need to find the minimal value for prescaler such that * * period_ns * clkrate - * ------------------------------ + * ------------------------------ < max_arr + 1 * NSEC_PER_SEC * (prescaler + 1) * - * isn't bigger than max_arr. + * This equation is equivalent to + * + * period_ns * clkrate + * ---------------------------- < prescaler + 1 + * NSEC_PER_SEC * (max_arr + 1) + * + * Using integer division and knowing that the right hand side is + * integer, this is further equivalent to + * + * (period_ns * clkrate) // (NSEC_PER_SEC * (max_arr + 1)) ≤ prescaler */ prescaler = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), - (u64)NSEC_PER_SEC * priv->max_arr); - if (prescaler > 0) - prescaler -= 1; - + (u64)NSEC_PER_SEC * ((u64)priv->max_arr + 1)); if (prescaler > MAX_TIM_PSC) return -EINVAL; prd = mul_u64_u64_div_u64(period_ns, clk_get_rate(priv->clk), (u64)NSEC_PER_SEC * (prescaler + 1)); + if (!prd) + return -EINVAL; /* * All channels share the same prescaler and counter so when two @@ -444,8 +452,9 @@ static int stm32_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, enabled = pwm->state.enabled; - if (enabled && !state->enabled) { - stm32_pwm_disable(priv, pwm->hwpwm); + if (!state->enabled) { + if (enabled) + stm32_pwm_disable(priv, pwm->hwpwm); return 0; } @@ -673,7 +682,8 @@ static int stm32_pwm_probe(struct platform_device *pdev) * .apply() won't overflow. */ if (clk_get_rate(priv->clk) > 1000000000) - return dev_err_probe(dev, -EINVAL, "Failed to lock clock\n"); + return dev_err_probe(dev, -EINVAL, "Clock freq too high (%lu)\n", + clk_get_rate(priv->clk)); chip->ops = &stm32pwm_ops; diff --git a/drivers/pwm/pwm-visconti.c b/drivers/pwm/pwm-visconti.c index 9e55380957be..28fae4979e3f 100644 --- a/drivers/pwm/pwm-visconti.c +++ b/drivers/pwm/pwm-visconti.c @@ -170,6 +170,7 @@ static struct platform_driver visconti_pwm_driver = { }; module_platform_driver(visconti_pwm_driver); +MODULE_DESCRIPTION("Toshiba Visconti Pulse Width Modulator driver"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Nobuhiro Iwamatsu <[email protected]>"); MODULE_ALIAS("platform:pwm-visconti"); diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 60b92c2c75ef..f8c2dc12dbd3 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -4,9 +4,12 @@ #include <linux/device.h> #include <linux/err.h> +#include <linux/module.h> #include <linux/mutex.h> #include <linux/of.h> +MODULE_IMPORT_NS(PWM); + struct pwm_chip; /** @@ -249,9 +252,7 @@ struct pwm_capture { * @free: optional hook for freeing a PWM * @capture: capture and report PWM signal * @apply: atomically apply a new PWM config - * @get_state: get the current PWM state. This function is only - * called once per PWM device when the PWM chip is - * registered. + * @get_state: get the current PWM state. */ struct pwm_ops { int (*request)(struct pwm_chip *chip, struct pwm_device *pwm); @@ -407,10 +408,6 @@ void pwmchip_remove(struct pwm_chip *chip); int __devm_pwmchip_add(struct device *dev, struct pwm_chip *chip, struct module *owner); #define devm_pwmchip_add(dev, chip) __devm_pwmchip_add(dev, chip, THIS_MODULE) -struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, - unsigned int index, - const char *label); - struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *chip, const struct of_phandle_args *args); struct pwm_device *of_pwm_single_xlate(struct pwm_chip *chip, @@ -505,14 +502,6 @@ static inline int devm_pwmchip_add(struct device *dev, struct pwm_chip *chip) return -EINVAL; } -static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, - unsigned int index, - const char *label) -{ - might_sleep(); - return ERR_PTR(-ENODEV); -} - static inline struct pwm_device *pwm_get(struct device *dev, const char *consumer) { @@ -574,13 +563,6 @@ static inline void pwm_apply_args(struct pwm_device *pwm) pwm_apply_might_sleep(pwm, &state); } -/* only for backwards-compatibility, new code should not use this */ -static inline int pwm_apply_state(struct pwm_device *pwm, - const struct pwm_state *state) -{ - return pwm_apply_might_sleep(pwm, state); -} - struct pwm_lookup { struct list_head list; const char *provider; |